Question: Who was the head of the Inca Empire?
Paraphrase: Who was the head of the Inca Empire?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q28573 wdt:P35 ?obj . ?obj wdt:P31 wd:Q5 } 
Answer: Atahualpa, Huascar, Pachacútec, Túpac Inca Yupanqui, Huayna Capac